Preheat oven to 350F.,Heat butter over med-high heat and saute onions for 5 minutes.,Add flour and stir constantly for 3-5 more minutes or until you cook the lour taste out.,Gradually add milk stirring until blended.,In a large bowl mix together beans, soup, soy sauce, sour cream, swiss cheese, onion mixture and pepper.,Stir well.,______,Place into a casserole dish and sprinkle stuffing mix over the top.,Bake for 25 minutes.